Fresh start: replace with naxIO/netfox-cs-sample foundation

Complete replacement of the tactical-shooter project with the
netfox-cs-sample (MIT) — a CS 1.6 inspired multiplayer FPS built
with Godot 4 and netfox.

## What's new
- Full CS-style gameplay: teams (T/CT), rounds, economy, buy menu
- 6 weapons: Knife, Glock, USP, AK-47, M4A1, AWP
- Bomb plant/defuse with 2 bombsites
- Flashbang & smoke grenades
- Proper netfox rollback netcode at 64 tick
- Network popup UI for host/join
- HUD, crosshair, round timer, scoreboard
- All netfox singletons registered as autoloads (works in exported builds)

## Architecture
- Listen-server (host from client, no dedicated server binary)
- Multiplayer-fps game lives at examples/multiplayer-fps/
- Netfox addons registered as autoloads for exported build compat
- Godot 4.7 with Forward+ renderer

## Removed
- Old headless-server architecture (client_main, server_main, player.gd, etc.)
- Custom netfox bootstrap with ENet fallback
- Old ChaffGames FPS template (2,420 lines, 844 KB)
- SimulationServer GDExtension stub
- Godot-jolt physics (netfox sample uses default Godot physics)
- Duplicate weapon_data.gd, anti_cheat.gd, round_manager.gd, etc.
- Server browser API Python venv (87 MB)
- test_range map and modular assets

## Preserved
- Git history
- Server config at config/default_server_config.cfg
- Windows export preset
- Build directory (gitignored)

Co-authored-by: naxIO <naxIO@users.noreply.github.com>

examples/forest-brawl/scripts/aura-sphere-mesh.gd

@@ -0,0 +1,49 @@
+@tool
+extends ArrayMesh
+class_name AuraSphereMesh
+
+@export var segments: int = 64:
+	set(v):
+		segments = v
+		regenerate()
+
+@export var rings: int = 32:
+	set(v):
+		rings = v
+		regenerate()
+
+@export var radius: float = 1.0:
+	set(v):
+		radius = v
+		regenerate()
+
+@export var material: Material:
+	set(v):
+		material = v
+		surface_set_material(0, material)
+
+func _init():
+	regenerate()
+
+func regenerate():
+	clear_surfaces()
+	var sphere = SphereMesh.new()
+	sphere.radial_segments = segments
+	sphere.rings = rings
+	sphere.radius = radius
+	sphere.height = 2 * radius
+	sphere.is_hemisphere = false
+	
+	var arrays = sphere.get_mesh_arrays()
+	var positions: PackedVector3Array = arrays[Mesh.ARRAY_VERTEX]
+	var uvs: PackedVector2Array = arrays[Mesh.ARRAY_TEX_UV]
+	
+	for i in range(uvs.size()):
+		var uv = positions[i]
+		uv = Vector2(uv.x, uv.y) / radius
+		uv = (Vector2.ONE + uv) / 2.0
+		
+		uvs.set(i, uv)
+	
+	add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, arrays)
+	surface_set_material(0, material)